1. Field of the Invention
The present invention relates to an information processing apparatus including a storage device, a control method of the information storage apparatus, and a program.
2. Description of the Related Art
In an image forming apparatus, a storage function, which includes a mass-storage device such as a hard disk drive (HDD) and stores image data scanned by a scanner unit, has been realized. Further, a function capable of storing data other than the scanned image data, received from a personal computer terminal in the above HDD has been also realized, so that the image forming apparatus very often functions as a storage.
Further, since important data is stored in a mass-storage device, it is necessary to secure safety of these data. Thus, for example, Japanese Patent Application Laid-Open No. 2005-149025 discusses a technique to realize a function to perform encryption of data by attaching an encryption board to a mass-storage device in an image forming apparatus.
In the aforementioned image forming apparatus, when encrypted data stored in an mass-storage device is backed up to another storage by using the encryption board, there have been a problem illustrated in FIG. 6.
FIG. 6 illustrates conventional backup processing and restoring processing of data. FIG. 6A corresponds to the backup processing and FIG. 6B corresponds to the restoring processing.
In FIG. 6A, a storage S1 is an HDD and a storage S2 is a semiconductor storage device, for example, a flash disk or an external storage connected to a universal serial bus (USB) controller 108 as a destination. The storage S2 is a storage for backing up data stored in the storage S1.
The storage S1 stores encrypted data AD and backs it up to the storage S2 as illustrated in FIG. 6A. The stored encrypted data AD is read into a memory M. Since the encrypted data AD backed up in the memory M has passed through an encryption board B, the data is decrypted and becomes plain text data RD. Thus, when the encrypted data AD read into the memory M is written in the storage S2, the plain text data RD is backed up to the storage S2. In other words, the encrypted data AD stored in the storage S1 is backed up to the storage S2 as the plain text data. Therefore, it becomes difficult to retain security of the backed up data.
Further, in FIG. 6B, there is the encrypted data AD in the storage S2 and the data is restored to the storage S1.
In this case, the encrypted data AD is read from the storage S2 into the memory M. There is the encrypted data AD on the memory M and the data AD is written in the storage S1. Since the encrypted data AD read into the memory M passes through an encryption board B, the data AD is further encrypted and restored to the storage S1 as doubly encrypted data AAD.
To deal with such a situation, an encryption board can be attached to the other storage. However, two encryption boards are used in this case, so that a production cost increases. Further, it is not realistic to doubly manage keys used in encryption/decryption.